Process for producing holes

ABSTRACT

A method of producing holes in a component, in particular of turbomachines, wherein each hole extends from a first, outer surface to a second, inner surface of the component and wherein the method has, for example, the following steps: producing a 3D model of the actual geometry of the component, at least for the region of the holes; adopting each hole on the basis of the actual geometry of the component; generating a production program for each individual hole. In this way, the process quality and with it the quality of the holes increases, because the offset of holes caused by component tolerances is avoided and the drilling funnels are formed according to specification. Furthermore, drilling defects on account of the offset of holes and/or cores can be avoided. Overlapping holes caused by component tolerances are likewise avoided.

RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/DE2006/001497 (International Publication Number WO 2007/028355),having an International filing date of Aug. 26, 2006 entitled “Method ofProducing Holes”. International Application No. PCT/DE/2006/001497claimed priority benefits, in turn, from German Patent Application No.10 2005 042 270.5, filed Sep. 6, 2005. International Application No.PCT/DE/2006/001497 is hereby incorporated by reference herein in itsentirety.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[Not Applicable]

MICROFICHE/COPYRIGHT REFERENCE

[Not Applicable]

BACKGROUND OF THE INVENTION

The present technology relates generally to a process for producingholes in a component, in particular in a turbo engine, where each holeextends from a first surface at the exterior of the component to asecond surface at the interior of the component. Furthermore, aproduction arrangement for carrying out the process is specified.

EP 1 246 711 131 describes, for example, such a process for producing anaperture, formed as a hole for cool air, in a metallic component of agas turbine, where in that component the aperture comprises, at least incertain portions, a funnel which is formed so as to be non-cylindrical,extends from a first surface to a second surface of the component, andis formed with a laser beam.

Cool air holes have a close spacing, in the case of new types ofcomponents go into the component at different angles, and, in part,closely follow the wall geometry. Tolerances of the outer geometry, e.g.in blade profiles, and of the inner geometry, e.g. in cavities or cores,as well as the inconsistency between them make process-stable productiondifficult. Furthermore, process-stable production is made difficultbecause the tolerances of the outer surface cause shifting, twisting, ortilting of the component, which has an effect on the position and shapeof the cool air holes.

According to the known state of the art, the holes are produced on thebasis of the nominal geometry. The tolerances which are entailed in theclamping process are eliminated in part by measuring the component,which is usually done with tactile sensing devices. In so doing, thetolerances of the outer and inner geometries, such as cavities andcores, have previously not been taken into consideration.

In regard to position and shape, great demands are made on cool airholes, in particular on funnel-shaped holes, in order to achieve thespecified cooling power for the component. If, for example, they are toosmall due to an inadequately formed funnel, then this can lead to animpermissible overheating of the component and to its failure. This inturn can cause a breakdown of the entire turbo system. This applies toproducing new parts as well as to maintenance, repair, and overhaul(MRO).

BRIEF SUMMARY OF THE INVENTION

Thus, one aspect of the presently described technology is to improve theprocess stated in the background. In particular, a process is providedin which one avoids inadequately formed funnel geometries at the outersurface, incompletely drilled holes, misalignment of the exit aperturesof the holes, drilling through the walls of the inner geometry, and themerging of holes due to the component tolerances, which are very largein comparison to the dimensions of the cool air holes. These outcomesand inexpected advantages can be realized according to the presenttechnology by a process with the features of the description containedherein and the appended claims, for example, claim 1 and a productionarrangement with the features of claim 10. Advantageous extensions ofthe present technology are specified in the subordinate claims.

Through the specified realization the quality of processing, and with itthe quality of the holes, increases because the misalignment caused bythe component tolerances is avoided and the drilled funnels are formedaccording to specification. Furthermore, drilling through the walls ofthe inner geometry due to the misalignment of the holes and/or the coresis avoided. Merging holes caused by component tolerances are alsoavoided. This allows one skilled in the art to appreciate an increase ofthe service lifetime of the component. Reprocessing costs and rejectcosts are eliminated or reduced. Only raw parts which lie withinspecification reach the processing stage. The expense in the finalcontrol is reduced due to the high process-stability after the testingfor the holes.

These and other features and advantages of the presently describedtechnology will be further understood and appreciated by those skilledin the art by reference to the following description, claims andappended drawings, if any. A more detailed description of the presenttechnology shall be discussed further below.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a perspective representation of a turbine blade of a gasturbine with apertures formed as cool air holes.

FIG. 2 is a first extract from a component of the present technology ina schematic cross-sectional view.

FIG. 3 is a second extract of a component of the present technology in aschematic cross-sectional view.

DETAILED DESCRIPTION OF THE INVENTION

According to the presently described technology, a process for producingholes in a component, in particular of turbo engines, where each holeextends from a first surface at the exterior of the component to asecond surface at the interior of the component, comprises the followingsteps:

-   -   developing a 3-D model of the geometry of the component, at        least for the area of the holes;    -   adapting each hole on the basis of, the actual geometry of the        component;    -   generating a production program for each individual hole.

The production of cool air holes requires that the outer and innergeometries (cavities in the turbine blade) of the individual part areknown. This is provided via a 3-D model of the individual component. A3-D model can be a surface model or a volume model. A 3-D model can bedeveloped via computer tomography (CT) but other processes are alsoconceivable. If the precision of the CT for the outer geometry isinadequate, then it is generated via an optical measurement process. CTand data from the optical process are linked to the 3-D model. In sodoing, it is also sufficient to transfer into the 3-D model only theextracts which are necessary for producing holes in the individualcomponent and its orientation (for example, 6-point nest).

On the basis of the 3-D model of the individual component each hole isadapted to the actual geometry within defined limits, where these limitscan be the tolerances, (position, diameter, length of the cylinder,depth of the funnel, width of the funnel, length of the funnel, angle ofthe funnel) by shifting the pattern of holes or the individual hole orgroup of holes, tilting the hole, displacing the hole, adapting thediameter, shifting the diffuser in the axis of the hole, tilting thediffuser with axis of the hole, or adapting the angle of the diffuser.

In this way it is achieved that one avoids the misalignment of the exitof the hole due to the tolerance of the outer geometry (for example, airfoil), whereby the covering of the component with the cooling filmremains unaffected. Furthermore, a funnel shape according tospecification is achieved despite the tolerance of the outer geometry,which has an effect on the funnel shape. Furthermore, drilling throughthe walls of the inner geometry due to tolerances of the inner geometry(cavity or core or core misalignment) is avoided. Furthermore, mergingholes or an undershoot of minimum spacings due to the tolerances of theraw part are avoided. One eliminates, or reduces the effect on theposition and shape of the cool air holes which is due to the componentsshifting, twisting, or tilting with respect to its nominal position,said shifting, twisting, or tilting being due to the tolerances of theouter surfaces on which the bases are formed (application point, 6-pointnest). Furthermore, there is the possibility of producing holes at shortdistance of the other geometry. Due to the knowledge of the actualgeometry the system for producing holes can be controlled so that beforea shot through/breakthrough into the interior space the power for theproduction process is reduced. This avoids drilling through the othergeometry. If the drilling process is stable, then the actual drillingdepth can be calculated. If the process is insufficiently stable, thenan in-process measurement of the drilling depth is made. In this wayprocess-stable production of holes becomes possible, which is notpossible, or not possible in a process-stable manner, in the case ofprior-art processes due to the low back-feeding (laser drilling) or tosmall a distance to the adjacent contour (erosion, electrochemicaldrilling). This is useful in particular in the case of small blades ofhelicopter engines or engines of business jets since there thetolerances are higher in relation to the dimensions of the componentthan in the case of larger blades. Finally, the possibility is providedof introducing holes into a component already partially provided withholes (for example, in the case of MRP tasks) in a manner which isadapted to the holes which are already present.

After the adaptation the production programs are generated withtraversing motions, removal volumes, and process parameters (feed rate,power, etc.) for the drilling processes for each individual hole of therespective component. These parameters can be ensured by testing. Thismakes possible the options that storing the production programs for eachindividual component can be dispensed with or that only storing of thetransformation matrices and the process parameters per component isnecessary.

The deviation in position of each individual component in the clampingdevice, said deviation being caused by systematic errors of the clampingdevice, is advantageously corrected numerically. The variation in theclamping process, in so far as necessary, can also be determined via ameasurement and corrected numerically. The component is defined in themachine producing the holes, except for the uncertainty of themeasurement, which with the correct choice of the means of measurementand the process parameters is negligible.

Via a comparison between the nominal 3-D model of the component and the3-D model with the actual geometry of the individual component it isdetermined whether adaptations are necessary. This step can, however,also be dispensed with if no changes are necessary.

Furthermore, a production arrangement according to the presentlydescribed technology for producing holes in a component, in particularof turbo engines, e.g. a hole-producing system, where each hole extendsfrom a first surface at the exterior of the component to a secondsurface at the interior of the component, is characterized by the factthat the arrangement comprises a central computer unit which isconnected to a device for developing a 3-D model of the actual geometryof the component. Furthermore, the production arrangement comprisesdevices for automatically adapting the hole on the basis of the actualgeometry of the component and devices for automatically generatingproduction programs for each individual hole. With this arrangement, theprocess of the present technology can be carried out.

Advantageously, the central computer unit is connected to a device forautomatically correcting the deviation of the component's position inthe clamping device.

Furthermore, an advantageous extension of the production arrangementaccording to the present technology is characterized by the fact that anautomatic drilling tool is connected to the computer unit. The drillingtool can be provided for cutting, for electrochemical removal, or forerosion.

Additional measures improving the present technology are represented inmore detail below together with the description of a preferredembodiment example of the present technology with the aid of thefigures.

Refer now to FIGS. 1-3. The figures are schematic representations andserve to explain the present technology. The same and similar componentsare represented by the same reference numbers. The specifications ofdirections relate to the turbo engine, unless otherwise specified.

FIG. 1 shows, in perspective representation and as a component, aturbine blade 1 of a gas turbine, such as, for example, an aircraftengine, in which numerous apertures 2 formed as cool air holes have beenformed according to the process according to the present technology. Thecool air holes 2 run in general through the component wall 3 at an acuteangle, which usually lies in the range of 12° to 35° with respect to theouter surface 4 of the component 1 and, for example, is 30°. From acavity in the turbine blade 1 air from the compressor is conductedthrough the cool air holes 2 in order to conduct a film of cool air overthe outer surface 4 of the turbine blade 1.

The turbine blade 1 consists of a metal, such as, for example, anNi-based or Co-based alloy, but can also consist of a ceramic materialand another heat-resistant material, and for the production of cool airholes 2 is clamped in a processing machine in which it can be traversedor turned along several axes. The relative motion between a drillingtool with which the forming of the cool air holes 2 is done and thecomponent 1 to be processed is in general produced by moving thecomponent 1. Likewise, this can be achieved, in general, by a morelimited motion of the drilling tool or a superimposed motion.

FIG. 2 shows an extract from component 1 in a schematic cross-sectionalview. Therein the actual geometry of the outer surface 7 is representedwith a thin line width and the nominal geometry of the outer surfacewith a thick line width. In this way the actual basis for the production8 and the nominal basis for the production 6 are defined. Furthermore,an inner surface 9 is represented, which in the present embodimentexample bounds a cooling duct reaching through to the rotor.

Depending on the choice of the production basis, nominal basis or actualbasis 8, either a hole 11 on the actual basis or a hole 10 on thenominal basis, with corresponding hole axes 13, 12, is generated. By thechoice of the actual basis drilling through the rear wall of the innersurface 9 is avoided.

FIG. 3 shows a second extract from component 1 in a schematiccross-sectional view, said component corresponding in essence to thecomponent represented in FIG. 2. In contradistinction thereto thecomponent in FIG. 3 comprises a second hole 16, 17, which compriseseither a hole axis 15 based on the actual basis or a hole axis 14 basedon the nominal basis. By the choice of the actual basis drilling throughthe rear wall and merging of holes is avoided.

With the production process according to the present technology, a holeon the actual basis is generated. In this way one eliminates the effecton the position and shape of the cool air holes which is due toshifting, twisting, or tilting of the component with respect to itsnominal position, said shifting, twisting, or tilting being due to thetolerances of the outer surfaces on which the bases are formed(application point, 6-point nest). In addition, merging holes anddrilling through the rear wall caused by tolerances, by outer and innergeometry, and the shifting and tilting of the inner and outer geometryare avoided.

The invention has now been described in such full, clear, concise andexact terms as to enable any person skilled in the art to which itpertains, to practice the same. It is to be understood that theforegoing describes preferred embodiments and examples of the inventionand that modifications may be made therein without departing from thespirit or scope of the invention as set forth in the claims. Moreover,while particular elements, embodiments and applications of the presenttechnology have been shown and described, it will be understood, ofcourse, that the present technology is not limited thereto sincemodifications can be made by those skilled in the art without departingfrom the scope of the present disclosure, particularly in light of theforegoing teachings and appended claims. Moreover, it is also understoodthat the embodiments shown in the drawings, if any, and as describedabove are merely for illustrative purposes and not intended to limit thescope of the invention, which is defined by the following claims asinterpreted according to the principles of patent law, including theDoctrine of Equivalents. Further, all references cited herein areincorporated in their entirety.

1. A process for producing holes in a component, wherein each holeextends from a first surface at the exterior of the component to asecond surface at the interior of the component and wherein the processcomprises the following steps: developing a 3-D model of the geometry ofsaid component, adapting each hole on the basis of said geometry of thecomponent; and generating a production program for each individual hole.2. The process according to claim 1 wherein the geometry of saidcomponent is the actual geometry.
 3. The process according to claim 2,wherein said component is a turbo engine.
 4. The process according toclaim 2, wherein said 3-D model of the geometry is developed for thearea of the holes.
 5. The process according to claim 1, furthercomprising correcting the deviation of the position of the component ina clamping device.
 6. The process according to claim 5, wherein thecorrection of deviation is based on the geometry of the outer surface ofthe component.
 7. The process according to claim 1, further comprisingthe additional step of at least one of calculating and measuring thedrilling depth of at least one hole.
 8. The process according to claim4, further comprising the additional step of at least one of calculatingand measuring the drilling depth of at least one hole.
 9. The processaccording to claim 5, further comprising the additional step of at leastone of calculating and measuring the drilling depth of at least onehole.
 10. The process according to claim 1, wherein said step ofgenerating a production program further comprises developing and storingprocess parameters and at least one transformation matrix.
 11. Theprocess according to claim 5, wherein said step of generating aproduction program further comprises developing and storing processparameters and at least one transformation matrix.
 12. The processaccording to claim 6, wherein said step of generating a productionprogram further comprises developing and storing process parameters andat least one transformation matrix.
 13. The process according to claim7, wherein said step of generating a production program furthercomprises developing and storing process parameters and at least onetransformation matrix.
 14. The process according to claim 8, whereinsaid step of generating a production program further comprisesdeveloping and storing process parameters and at least onetransformation matrix.
 15. The process according to claim 9, whereinsaid step of generating a production program further comprisesdeveloping and storing process parameters and at least onetransformation matrix.
 16. The process according to claim 1, whereinsaid developing a 3-D model step further comprises using computertomography to develop said 3-D model of the geometry of the component.17. The process of claim 16 wherein said geometry of the component isthe actual geometry.
 18. The process according to claim 5, wherein saiddeveloping a 3-D model step further comprises using computer tomographyto develop said 3-D model of the geometry of the component.
 19. Theprocess of claim 18 wherein said geometry of the component is the actualgeometry.
 20. The process according to claim 6, wherein said developinga 3-D model step further comprises using computer tomography to developsaid 3-D model of the geometry of the component.
 21. The process ofclaim 20 wherein said geometry of the component is the actual geometry.22. The process according to claim 7, wherein said developing a 3-Dmodel step further comprises using computer tomography to develop said3-D model of the geometry of the component.
 23. The process of claim 22wherein said geometry of the component is the actual geometry.
 24. Theprocess according to claim 8, wherein said developing a 3-D model stepfurther comprises using computer tomography to develop said 3-D model ofthe geometry of the component.
 25. The process of claim 24 wherein saidgeometry of the component is the actual geometry.
 26. The processaccording to claim 9, wherein said developing a 3-D model step furthercomprises using computer tomography to develop said 3-D model of thegeometry of the component.
 27. The process of claim 26 wherein saidgeometry of the component is the actual geometry.
 28. The processaccording to claim 1, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 29. The process of claim 28 whereinsaid geometry of the component is the actual geometry.
 30. The processaccording to claim 5, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 31. The process of claim 30 whereinsaid geometry of the component is the actual geometry.
 32. The processaccording to claim 6, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 33. The process of claim 32 whereinsaid geometry of the component is the actual geometry.
 34. The processaccording to claim 7, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 35. The process of claim 34 whereinsaid geometry of the component is the actual geometry.
 36. The processaccording to claim 8, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 37. The process of claim 36 whereinsaid geometry of the component is the actual geometry.
 38. The processaccording to claim 9, wherein said developing a 3-D model step furthercomprises using an optical measuring process to develop said 3-D modelof the geometry of the component.
 39. The process of claim 38 whereinsaid geometry of the component is the actual geometry.
 40. The processaccording to claim 10, further comprising the step of using respectivetransformation of a set of sample data to produce one or more componentshaving a similar geometry in parallel.
 41. The process according toclaim 10, wherein said production program comprises at least one oftraversing paths, removal volumes and process parameters.
 42. Theprocess according to claim 1, wherein the holes are generated by atleast one of cutting, laser removal, electrochemical processing, anderosion.
 43. The process according to claim 5, wherein the holes aregenerated by at least one of cutting, laser removal, electrochemicalprocessing, and erosion.
 44. The process according to claim 6, whereinthe holes are generated by at least one of cutting, laser removal,electrochemical processing, and erosion.
 45. The process according toclaim 7, wherein the holes are generated by at least one of cutting,laser removal, electrochemical processing, and erosion.
 46. The processaccording to claim 8, wherein the holes are generated by at least one ofcutting, laser removal, electrochemical processing, and erosion.
 47. Theprocess according to claim 9, wherein the holes are generated by atleast one of cutting, laser removal, electrochemical processing, anderosion.
 48. A production arrangement for producing holes in acomponent, said arrangement comprising: a central computer unitconnected to a device for developing a 3-D model of the geometry of thecomponent; at least one device for automatically adapting each holebased on the geometry of the component; and at least one device forautomatically generating production programs for each hole; wherein eachhole extends from a first surface at the exterior of the component to asecond surface at the interior of the component.
 49. The productionarrangement of claim 48 wherein said geometry of the component is theactual geometry.
 50. The production arrangement of claim 48, whereinsaid component is a turbo engine.
 51. The production arrangementaccording to claim 48, further comprising an automatic drilling toolconnected to the computer unit.